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koy23 - Flow Rate Analysis
#11
RE: Do I increase pressure till flow limit disappear?
I'm not sure if my issue was similar to yours, but mine was definately due to abrupt air push when in the brink of falling asleep.

Looking back, I think it was related to leaks that happen inside the mouth (the kind that can cause chipmunk cheeks at the extreme). It happens when I'm on my back and mainly when using full face masks.

Now that I wear nasal masks with no mask over my mouth, I do get leaks inside the mouth sometimes. And I know it happens when I'm on the brink of falling asleep as my muscles relax and so does my tongue that block the air leaking inside my mouth.

Your OSCAR chart looks great, and only culprit I see from it is the leaks. It's likely related to the sharp spike leaks. You should see if these leak timing correlate to your 'spasms.'

With nasal masks, I believe these leaks are very obvious, but with full face masks, it's an odd pressure response that's hard to pinpoint what it is exactly, but I believe both are caused by the same issue, the tongue release that pressure inside the mouth. Could it be that? Could it be sudden leaks that is what you maybe thinking as spasms?


I also use fixed pressure because beyond a threshold, there's higher occurrence of inside the mouth leaks. And we all know that Resmed's FL detection isn't great and it can spike pressure for no good reason. Therefore, I use fixed pressure to prevent their 'algorithm' from working.
#12
RE: Do I increase pressure till flow limit disappear?
[attachment=37932 Wrote:sheepless pid='425394' dateline='1639345371']'jerking awake' may have nothing to do with pressure.

with vauto, min pressure support is the setting to address flow limitations. some people are more sensitive to flow limitations than others but yours are so minor I don't think it's your problem. with fixed pressure I don't see how pressure changes can be a factor. if you've experienced arousals after a bump of .2 cmw, my guess is that it's the result, not the cause of your arousal. both screenshots are really good charts but higher pressure produced more mouth leaks so why not leave it lower.

to figure out why you're awakening, make a note of when you wake. stop flow for a minute, spike a huge breath or leak, speak to a voice activated audio recorder, use a video camera... then you can scroll through your flow rate at various view scales (I suggest 10 minutes and 3 minutes) looking for clues, especially in the few minutes leading up to the awakening. you're looking for disordered breathing, events, pauses that are less than 10 seconds, big flow limitations, leaks and repetitive patterns.

(12-12-2021, 05:08 PM)Sleeprider Wrote: I think it would be helpful to see what pattern you are concerned with. You have been a member here for quite a while, and I'm sure you know we normally use pressure support to deal with flow limitation (inspiratory flattening), rather than just pressure.  Basically once obstructive apnea is resolved, EPAP should not need to be raised significantly.  I think at one time you also had aerophagia and now this mouth-leak.  Both of those conditions argue against pressure increases.  

Sleep disruption is often unrelated to PAP therapy, and as you say, your arousals occur despite therapy.  If your respiration and pressure are cruising along without a lot of disruption, and an arousal occurs, it is hard to connect that to your use of PAP.  There are many causes of arousal including limb movement and even just a need to change sleep position. Happens to me all the time, and it can be hard to return to sleep.  Anyway, let's get a look at what is currently going on in Oscar.

(12-12-2021, 09:26 PM)SarcasticDave94 Wrote: I would use New Attachment below the textbox to add OSCAR. The one from Imgur is ok but attaching them places the chart right in the post. If it's the chart I looked at, there's random high leaks that's a bigger issue than flow limits.

(12-13-2021, 12:02 PM)sheepless Wrote: "I think its the same thing to put it on max epap 8 and min epap 6 with PS 2 than in cpap mode with pressure 8 and EPR 2. Right, same thing?"

1st, I've never used my vauto in cpap mode so I didn't even know it has an epr setting (thanks, good to know!). 2nd, in vauto mode, min 8, max 8, ps 2 would be the same as cpap mode pressure 8, epr 2. 3rd, while epr seems to work like ps, I've never read any authoritative sources confirming epr is as effective as ps (not that I've looked very hard). resmed says it's a comfort feature. minor points. oh, another minor point for the sake of clarity, the apap us called airsense 10 autoset, vauto is aircurve 10 vauto. :-)

"I think in vauto mode it actually "syncs" little better to my breath cycle if that makes any sense!"

I'm confused by this. if vauto mode syncs better, why are you using cpap mode?

I followed the advice and used my nasal mask ( no leaks) with PS of 2, made marks each time I woke up by shutting off the machine or breathing 5 deep breaths, I also added my own flags but not sure if they were done right, i followed the air flow zoomed in and took these screenshots:

I have no idea how to interpret them, or to what caused the waking ups!
Also don't know what are these rhytmic spikes ( you wil lsee in the screenshots)

hope you guys can analyze them better than I could and maybe direct me to what i can do ?

thanks
P.S: sorry for the many screenshots, trying to be as accurate as possible.


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#13
RE: Do I increase pressure till flow limit disappear?
I used to get those spikes and it was from hypnic jerks. It went away after awhile, so I really don't know how it stopped. At the time, my sleep quality was bad.
#14
RE: Do I increase pressure till flow limit disappear?
(12-12-2021, 04:42 PM)sheepless Wrote: 'jerking awake' may have nothing to do with pressure.

with vauto, min pressure support is the setting to address flow limitations. some people are more sensitive to flow limitations than others but yours are so minor I don't think it's your problem. with fixed pressure I don't see how pressure changes can be a factor. if you've experienced arousals after a bump of .2 cmw, my guess is that it's the result, not the cause of your arousal. both screenshots are really good charts but higher pressure produced more mouth leaks so why not leave it lower.

to figure out why you're awakening, make a note of when you wake. stop flow for a minute, spike a huge breath or leak, speak to a voice activated audio recorder, use a video camera... then you can scroll through your flow rate at various view scales (I suggest 10 minutes and 3 minutes) looking for clues, especially in the few minutes leading up to the awakening. you're looking for disordered breathing, events, pauses that are less than 10 seconds, big flow limitations, leaks and repetitive patterns.

(12-14-2021, 06:48 AM)CorruptAlligator Wrote: I used to get those spikes and it was from hypnic jerks.  It went away after awhile, so I really don't know how it stopped.  At the time, my sleep quality was bad.

That is what i was complainging about before, I always said the cpap increased my "spasms" , now i have to wear it as i snore awake as soon as I fall asleep, so wonder if there was a setting that made those hypnic jerks less for you ?
#15
RE: Do I increase pressure till flow limit disappear?
I can't say exactly what, but I stopped wearing FFM, started using nasal masks, and started sleeping on my side.

Do you sleep on your back? If so, I recommend sleepin on the side.

You can try weighted blankets as well, until it truely goes away. I believe the point of weighted blankets are reducing sensations to take mind off them. Are you heavily sleep deprived? It can't be airway collapsing since your FL are fine. I've read these jerks are caused from heavy sleep deprivation.
#16
RE: Do I increase pressure till flow limit disappear?
it's not clear to me what we're seeing in these charts. could be hypnic jerks, maybe simple involuntary inhales my doc described to me as a sort of shakey yawn, when awake at least (consistent with excessive tiredness). I wouldn't expect those to wake you or leave you feeling unrested though. they aren't followed by the larger ragged breathing we'd associate with an arousal.

I can't easily enlarge the charts to figure the timing but the spikes are regular enough that they could be related to periodic limb movement. elsewhere your flow rate rises and falls, dropping off quite a bit, also with some degree of periodicity. this could be very minor plm, uars flow limitations, or you might have a tendency toward central apnea that doesn't rise to the level necessary to be called central apnea. not very helpful but as I said, it's not clear to me what's waking you.

you may have awakened during your almost 11 hour session but not to the point of masking off. 11 hours is a long time; some say too much sleep can leave us as tired as too little.
  Shy   I have no particular qualifications or expertise with respect to the apnea/cpap/sleep related content of my posts beyond my own user experiences and what I've learned from others on this site. Each of us bears the burden of evaluating the validity and applicability of what we read here before acting on it.  
 
#17
RE: Do I increase pressure till flow limit disappear?
(12-12-2021, 04:42 PM)sheepless Wrote: 'jerking awake' may have nothing to do with pressure.

with vauto, min pressure support is the setting to address flow limitations. some people are more sensitive to flow limitations than others but yours are so minor I don't think it's your problem. with fixed pressure I don't see how pressure changes can be a factor. if you've experienced arousals after a bump of .2 cmw, my guess is that it's the result, not the cause of your arousal. both screenshots are really good charts but higher pressure produced more mouth leaks so why not leave it lower.

to figure out why you're awakening, make a note of when you wake. stop flow for a minute, spike a huge breath or leak, speak to a voice activated audio recorder, use a video camera... then you can scroll through your flow rate at various view scales (I suggest 10 minutes and 3 minutes) looking for clues, especially in the few minutes leading up to the awakening. you're looking for disordered breathing, events, pauses that are less than 10 seconds, big flow limitations, leaks and repetitive patterns.

(12-14-2021, 03:24 PM)sheepless Wrote: it's not clear to me what we're seeing in these charts. could be hypnic jerks, maybe simple involuntary inhales my doc described to me as a sort of shakey yawn, when awake at least (consistent with excessive tiredness). I wouldn't expect those to wake you or leave you feeling unrested though. they aren't followed by the larger ragged breathing we'd associate with an arousal.

I can't easily enlarge the charts to figure the timing but the spikes are regular enough that they could be related to periodic limb movement. elsewhere your flow rate rises and falls, dropping off quite a bit, also with some degree of periodicity. this could be very minor plm, uars flow limitations, or you might have a tendency toward central apnea that doesn't rise to the level necessary to be called central apnea. not very helpful but as I said, it's not clear to me what's waking you.

you may have awakened during your almost 11 hour session but not to the point of masking off. 11 hours is a long time; some say too much sleep can leave us as tired as too little.


let's skip the 11hrs thing bc it is not really 11 hrs (long story sigh..).
So if the spikes are not something to worry about, are you able to see what causes the arousals? I put like 7 graphs all marked with the 5 breatths/ or turnign off the machine. Can you see what happens in the flow rate to cause awaking? it looks like PS isn't really key here. do you suggest more pressure? more PS ? i'm really cluless on what to do next. I just ordered few FFM masks to see if i'll get less leaks.
#18
RE: Do I increase pressure till flow limit disappear?
(12-14-2021, 01:18 PM)CorruptAlligator Wrote: I can't say exactly what, but I stopped wearing FFM, started using nasal masks, and started sleeping on my side.

Do you sleep on your back?  If so, I recommend sleepin on the side.

You can try weighted blankets as well, until it truely goes away.  I believe the point of weighted blankets are reducing sensations to take mind off them.  Are you heavily sleep deprived?  It can't be airway collapsing since your FL are fine.  I've read these jerks are caused from heavy sleep deprivation.

both nasal and FFM show the spikes. I have had worse spasms in the last 3 years I could not even tolerate the CPAP, now i'm trying to find a workaround . sleep mostly on side but sometimes on back. I actually have a eighted blanket LOL. i think my sleep pattern has been corrupted from all the night arousals in the past 3 years.
#19
RE: Do I increase pressure till flow limit disappear?
your UF2's are interesting. those are the areas I mentioned in which your flow rate volume ebbs for a few breaths, possibly due to movement, possibly a tendency toward ca, possibly simple uars flow limitations. most or maybe all of the awakenings are preceded by these so those are the first things I'd try figure out. pauses shorter than 10 seconds precede awakenings in a couple places as well, maybe just enough to rouse you. these ebbs and pauses are associated with minor flow limitations. if you're using vauto, you could try incrementally bumping min ps to see if they even out. also, search the web for a tidal volume calculator. 380 is a bit low depending on your size and might benefit from a bit more pressure/pressure support as well but see what happens with a bit more min ps.
  Shy   I have no particular qualifications or expertise with respect to the apnea/cpap/sleep related content of my posts beyond my own user experiences and what I've learned from others on this site. Each of us bears the burden of evaluating the validity and applicability of what we read here before acting on it.  
 
#20
RE: Do I increase pressure till flow limit disappear?
(12-12-2021, 04:42 PM)sheepless Wrote: 'jerking awake' may have nothing to do with pressure.

with vauto, min pressure support is the setting to address flow limitations. some people are more sensitive to flow limitations than others but yours are so minor I don't think it's your problem. with fixed pressure I don't see how pressure changes can be a factor. if you've experienced arousals after a bump of .2 cmw, my guess is that it's the result, not the cause of your arousal. both screenshots are really good charts but higher pressure produced more mouth leaks so why not leave it lower.

to figure out why you're awakening, make a note of when you wake. stop flow for a minute, spike a huge breath or leak, speak to a voice activated audio recorder, use a video camera... then you can scroll through your flow rate at various view scales (I suggest 10 minutes and 3 minutes) looking for clues, especially in the few minutes leading up to the awakening. you're looking for disordered breathing, events, pauses that are less than 10 seconds, big flow limitations, leaks and repetitive patterns.

(12-14-2021, 07:13 PM)sheepless Wrote: your UF2's are interesting. those are the areas I mentioned in which your flow rate volume ebbs for a few breaths, possibly due to movement, possibly a tendency toward ca, possibly simple uars flow limitations. most or maybe all of the awakenings are preceded by these so those are the first things I'd try figure out. pauses shorter than 10 seconds precede awakenings in a couple places as well, maybe just enough to rouse you. these ebbs and pauses are associated with minor flow limitations. if you're using vauto, you could try incrementally bumping min ps to see if they even out. also, search the web for a tidal volume calculator. 380 is a bit low depending on your size and might benefit from a bit more pressure/pressure support as well but see what happens with a bit more min ps.

thanks, it seems that there is no obvious respiratory reason from the graphs then to what is causing arousals. I have been trying different pressures on and off wit hthe Vauto and never could acheive restful uninterrupted sleep, and gave up many times, also because i used to get those hypnic jerks as soon as I fall asleep with the machine, now it seems I can fall asleep without feeling the hypnic jerks too much but still wake up, mostly in REM no matter what pressure/settings ... so far.
I did have surgeries in my throat, so the area there I know is not really stable as well. 
but thanks for the direction.


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